E520 flash refuses to fire

The last couple of times I've used my E520, I couldn't get it to fire its flash. Tried the built-in flash as well as two different external hot-shoe mounted flashes. I even tried to shoot in Auto mode - the camera will pop up the built-in flash, indicate an orange flash symbol on the display, but then it doesn't fire.

Next, see if the strobing AF-assist will work. (You may have to re-enable it in your menu). Try it in a dim room, where the camera will have trouble focusing without some help. If focus assist works, you know your built-in flash is not burned out.

With the hot-shoe flashes, the trouble may be with dirty contacts. Clean them with a pencil-end eraser. Be sure to brush away any debris.

I just had a thought that if all of these still fail... did you use a 3rd-party flash with a high voltage and fry some circuitry? I hope that isn't the case.